Beta-blockers have been shown to worsen insulin resistance and deteriorate lipoprotein metabolism in hypertensive patients. However, beta-1 selective beta-blockers seem to offer some advantage over non-selective ones and the degree of beta-1 selectivity is of importance. Thirty patients with primary hypertension were treated with the highly beta-1 selective beta-blocker bisoprolol for three months. There was a highly significant reduction of the blood pressure but no changes in fasting plasma-glucose or plasma-insulin levels were observed.